Mask aligners and steppers (reductive projection exposure apparatus) are known as lithographic projection exposure apparatuses. The former is an apparatus for exposing a reticle mask pattern for a wide area at a time, and is an essential apparatus for fabrication of liquid crystal device, ensuring an accuracy of 0.8 μm or higher on the line-and-space basis. The latter stepper is dedicated to a semiconductor process, which reductively forms an image of a reticle mask pattern corresponding to each device size, ensuring an accuracy of 0.18 to 0.5 μm or around on the line-and-space basis.
Using the former mask aligner for research and development of devices, however, makes it difficult to rapidly repeat trial-and-error experiments since the reticle is very expensive and requires a very long time of period for delivery thereof. There is also known a relatively inexpensive manual-operation-type mask aligner, operation of which however requires a great deal of skill since alignment and so forth must be achieved manually, so that reproducibility in the experimental results tend to vary depending on the level of skill in the operation.
Also the latter stepper is not practical for use in research and development since it suffers not only from the same problems in the reticle fabrication, but also from problems that the apparatus is expensive, that a facility environment around the apparatus needs a very severe control, and that its full-automatic nature makes it difficult to be applied to purposes other than semiconductor process.
It is therefore an object of the present invention to provide a projection exposure apparatus for research and development, which is capable of readily transfer a desired pattern, and moreover featured by its compactness, inexpensiveness and easy operation.